The present invention relates to dispensers for aerosols or other pressurized products, and more particularly to a pressure resistant plastic bottle for dispensing an aerosol or other comparably pressurized product.
The term “aerosol” will be understood herein to mean any non-refillable receptacle containing a gas compressed, liquefied or dissolved under pressure, the sole purpose of which is to expel a nonpoisonous (other than a Division 6.1 Packing Group III material) liquid, paste, or powder and fitted with a self-closing release device allowing the contents to be ejected by the gas. Aerosol products include but are not limited to foamed or gel preparations or to liquid products delivered in a non-aerosol stream.
Pressurized containers for dispensing aerosols are well known in the art, and are typically constructed of metal in order to withstand the inherent internal pressure of aerosols. However, it is desirable to provide a plastic container capable of withstanding the internal pressures generated by an aerosol because plastic has many advantages over metal. Some of these advantages include the ease and economy of manufacture, aesthetic appeal to an end user, rust resistance, and the recyclability.
Such pressurized containers have a dispensing nozzle or dispensing orifice to allow the product to be dispensed from the package. The dispensing nozzle or dispensing orifice may be disposed near the top of the package, although other configurations and locations are also known in the art. Dispensing nozzle and dispensing orifice are typically designed to accommodate the product being dispensed (i.e. atomized sprays vs laminar flow gels and fluids). As a result, different valve designs are required to dispense different products. In addition dispensing nozzles are typically spring loaded actuators manufactured from metal in order to provide reliable components such as springs, valve cups and valve stems. Plastic pressurized containers including such valves are typically non recyclable.
Pressurized dispensers may have a variety of configurations, including bag-on-valve, bag-on-can or piston designs. In general, the container of the dispenser is divided by a barrier member into product and propellant chambers. The barrier member may be a bag sealed to the valve assembly, a bag sealed to the container wall, or a piston member slidably disposed within the container. Generally, the product is charged into the product chamber through the valve assembly, whereas the propellant is charged into the propellant chamber through either the valve assembly or a charging orifice provided on the container wall.
Because the valve assembly provides fluid passageways during the filling and dispensing operations of the pressurized dispenser, a valve assembly specifically designed to accommodate optimum efficiency of both operations is highly desirable. For example, increasing product flow through the valve assembly during the filling operation expedites the manufacturing process of the pressurized dispenser. However, the increased product flow may adversely affect the spray characteristics of the dispenser.
Thus, there is a need for a valve assembly that provides an increase flow rate during product filling while retaining a regular flow rate during product dispensing. In addition, there is a need for a universal valve assembly that can accommodate atomized sprays and laminar flow fluids and gels.